I’ve seen the following behavior a few times in the last weeks:
I’m reading topic A
I click a link to another suggested topic
the spinner shows for a moment
I’m back at the beginning of topic A
reloading the page shows topic B
After the bug is triggered, as long as the page isn’t reloaded, all navigation will always end in topic A.
This is happening in Safari in iOS. I don’t have definite repro steps, but navigating around with the suggested topic links seems to trigger it sometimes.
I haven’t seen it in the Discourse iOS app; I haven’t been testing in Safari lately. So maybe it’s fixed – the Safari view controller should be pretty identical to the real Safari.